From EP1874557 in the name of the applicant, a security document is known with a portrait image in the form of a number of interlaced line images. Groups of image lines are provided each time below a cylindrical lens by laser engraving in a polycarbonate base layer. Viewing the image results in a stereoscopic view of the security document holder. The image area in which the interlaced lines are formed by laser engraving and are covered by the lenses, which may be formed in the polycarbonate material by embossing, is rectangular.
From PCT/NL2014/050846, in the name of the applicant, a security document is known in which the lenses are formed by an array of spherical lenses in the image area, the image area comprising an array of image elements having a pitch that is different from the pitch of the lenses, resulting in an Moiré magnification of the image which is viewed below or above the image elements in the plastics material.
WO 2013/167887 discloses a security document provided with a pattern of lenses that are applied within a contour of letters D, L or R and a pattern of micro-images situated below the lenses.
The known security documents are difficult to illegally duplicate in view of the high precision process required for properly aligning the image formed in the image area with the lens structure. Alteration of a primary image of a known security document is detectable in view of difficult access to the image pattern in the image area below the lenses of the authentication image. The known security documents have as a disadvantage that the primary image, which gives information about the document holder, needs to be applied at the site of production of the security document. In case of an identity document, the primary image is often formed by a portrait image of the holder of the document. This means that completion of the security document such as by application of the authentication image or personalization data, requires the holder image to be forwarded to the production site of the document which may involve complex logistics.
It is therefore an object of the present invention to provide a security device such as a card or document having improved security features. It is a further object of the invention to provide a security device which may be produced and completed at one location and may be authenticated and/or personalized in an easy and secure manner at a location remote from the production site.